1. Technical Field
The present invention relates to an image capturing lens system. More particularly, the present invention relates to a compact image capturing lens system applicable to electronic products.
2. Description of Related Art
In recent years, with the popularity of mobile products with camera functionalities, the demand of miniaturized optical lens systems is increasing. The sensor of a conventional photographing camera is typically a CCD (Charge-Coupled Device) or a CMOS (Complementary Metal-Oxide Semiconductor) sensor. As the advanced semiconductor manufacturing technologies have allowed the pixel size of sensors to be reduced and compact optical lens systems have gradually evolved toward the field of higher megapixels, there is an increasing demand for compact optical lens systems featuring better image quality.
A conventional compact optical lens system in a portable electronic product mainly adopts a structure of three-element lens such as the one disclosed in U.S. Pat. No. 7,145,736. Due to the popularity of mobile products with high-end specifications, such as smart phones and PDAs (Personal Digital Assistants), the requirements for high resolution and better image quality of modern compact optical lens systems has been increasing significantly. However, the conventional three-element lens structure cannot satisfy these requirements of the compact optical lens system.
Although other conventional optical lens systems with four-element lens structure such as the one disclosed in U.S. Pat. No. 8,314,999. Although better image quality is obtained, the total track length of the optical lens system is thereby too long to maintain a compact size. Moreover, the design of the image-side surface of the second lens element makes the image quality of the peripheral region hard to control.